What is restrictive cardiomyopathy?
cardiomyopathy, the rarest form of cardiomyopathy, is a condition
in which the walls of the lower chambers of the heart (the
ventricles) are abnormally rigid and lack the flexibility to expand
as the ventricles fill with blood.
The pumping or systolic function of the ventricle may be normal
but the diastolic function (the ability of the heart to fill with
blood) is abnormal. Therefore, it is harder for the ventricles to
fill with blood, and with time, the heart loses the ability to pump
blood properly, leading to heart failure.
What are the symptoms of restrictive cardiomyopathy?
Many people with restrictive
cardiomyopathy have no symptoms or only minor symptoms, and live a
normal life. Other people develop symptoms, which progress and
worsen as heart function worsens.
Symptoms occur at any age and may include:
- Shortness of breath (at first with exercise; but over time it
occurs at rest)
- Fatigue (feeling overly tired)
- Inability to exercise
- Swelling of the legs and feet
- Weight gain
- Nausea, bloating, and poor appetite (related to fluid
- Palpitations (fluttering in the chest due to abnormal heart
Less common symptoms:
- Fainting (caused by irregular heart rhythms, abnormal responses
of the blood vessels during exercise, or no cause may be
- Chest pain or pressure (occurs usually with exercise or
physical activity, but can also occur with rest or after
What causes restrictive cardiomyopathy?
A restrictive cardiomyopathy is not usually inherited and its cause
is often unknown. Known causes may include:
- Build-up of scar tissue (idiopathic is the most common
- Build-up of abnormal proteins (amyloidosis) in the heart
- Chemotherapy or chest exposure to radiation
- Excess iron (hemochromatosis) in the heart
- Other systemic diseases (sarcoidosis)
How is restrictive cardiomyopathy diagnosed?
size of the heart may remain normal with restrictive
cardiomyopathy. In some cases, restrictive cardiomyopathy may be
confused with constrictive pericarditis, a condition in which the
layers of the pericardium (the sac that surrounds the heart) become
thickened, calcified, and stiff.
Restrictive cardiomyopathy is diagnosed based on medical history
(your symptoms and family history), physical exam, and tests such
as: blood tests, electrocardiogram, chest X-ray, echocardiogram,
exercise stress test, cardiac catheterization, CT scan, MRI and
radionuclide studies (Multigated Acquisition Scan).
A myocardial biopsy occasionally is done to determine the cause
of cardiomyopathy. During a myocardial biopsy, a small tissue
sample is taken from the heart and examined under a microscope to
examine the cause of the symptoms.